A linear guide mechanism includes an actuator side guide member, moving block side guide members disposed on both sides of the actuator side guide member, and a plurality of balls disposed in two rows, respectively, between the actuator side guide member and each of the moving block side guide members. Set screws that are capable of adjusting a pre-loading of the balls and are capable of improving the straightness of the moving block side guide members, are attached to a moving block.

A linear motion guide unit 1 includes a rail 10 having a pair of first rolling surfaces extending parallel to each other in a longitudinal direction, a slider 100 that fits over the rail in a relatively movable manner and has a pair of second rolling surfaces opposing the pair of first rolling surfaces, respectively, and a plurality of spheres as rolling elements 200 that roll while contacting the first and second rolling surfaces. The unit 1 has a loop path composed of a load-carrying race 102 formed with the first and second rolling surfaces, a first circulation passage 103 parallel to the load-carrying race and formed in the slider, and two second circulation passages 104 connecting the load-carrying race 102 and the first circulation passage 103, and the rolling elements 200 circulate through the loop path. The load-carrying race 102 has a load-carrying race first portion 102a at a boundary with the second circulation passage 104, and a contact angle θ.sub.1 of the rolling element 200 with the second rolling surface in the load-carrying race first portion 102a is greater than a contact angle θ.sub.2 of the rolling element with the second rolling surface in a portion of the load-carrying race 102 other than the load-carrying race first portion. The slider 100 includes a carriage 110, a pair of end caps 120 disposed to sandwich the carriage 110 therebetween in the longitudinal direction of the rail 10, and a spacer 130 disposed between at least one of the pair of end caps 120 and the carriage 110. The spacer 130 has the second rolling surface constituting the load-carrying race first portion 102a.

A linear guide mechanism includes an actuator side guide member, moving block side guide members disposed on both sides of the actuator side guide member, and a plurality of balls disposed in two rows, respectively, between the actuator side guide member and each of the moving block side guide members. Set screws are attached to a moving block.

A linear motion guide unit includes a rail having first rolling surfaces extending longitudinally parallel to each other, a movable slider fitting over the rail, second rolling surfaces opposing the first rolling surfaces, respectively, rolling elements that roll while contacting the first and second rolling surfaces, a loop path through which the rolling elements circulate composed of a load-carrying race formed with the first and second rolling surfaces, a first circulation passage formed in the slider parallel to the load-carrying race, and two second circulation passages connecting the load-carrying race and the first circulation passage. The load-carrying race has a first portion at a boundary with the second circulation passage, and a contact angle of the rolling element with the second rolling surface in the first portion is greater than a contact angle of the rolling element with the second rolling surface in a remaining portion of the load-carrying race.

A circulator structure includes a main body, a Y-like groove and two return channels. The main body has a first side surface, a second side surface and a through hole. The Y-like groove includes a first oil-guiding groove, a second oil-guiding groove and an oil distribution groove. The first oil-guiding groove and the second oil-guiding groove are located at two opposite sides of the through hole, and the oil distribution groove is located below the through hole. A lower guiding end of the first oil-guiding groove and a lower guiding end of the second oil-guiding groove are respectively connected to the oil distribution groove. The oil distribution groove has an upper end distribution opening connected to the through hole and a lower end distribution opening. The return channels are respectively located on two opposite sides of the first side surface and are connected to the lower end distribution opening.

A circulator structure includes a main body, a Y-like groove and two return channels. The main body has a first side surface, a second side surface and a through hole. The Y-like groove includes a first oil-guiding groove, a second oil-guiding groove and an oil distribution groove. The first oil-guiding groove and the second oil-guiding groove are located at two opposite sides of the through hole, and the oil distribution groove is located below the through hole. A lower guiding end of the first oil-guiding groove and a lower guiding end of the second oil-guiding groove are respectively connected to the oil distribution groove. The oil distribution groove has an upper end distribution opening connected to the through hole and a lower end distribution opening. The return channels are respectively located on two opposite sides of the first side surface and are connected to the lower end distribution opening.

A rolling guide apparatus having a first member 1, a second member 2, and a rolling body unit 5, the apparatus including a guide path G of the rolling body unit 5 including a rolling path R configured to have a rolling groove 1a and a rolling groove 3a, and a circulation path C allowing communication between a start point and an end point of the rolling path R, the rolling body unit 5 being configured to have a plurality of first rolling bodies 5a and a plurality of second rolling bodies 5b each composed of an elastic material, at least one second rolling body 5b being always positioned in the circulation path C. The rolling guide apparatus is easy to be assembled and is capable of performing stable operations.

A lubricant supply member of a linear guide includes a first recessed part formed above a guide rail, a pair of second recessed parts formed at both left and right side-surface positions of the guide rail, and protrusions slidable on rail side raceway surfaces of the guide rail. A lubricating unit includes a first cylindrical part, arranged in the first recessed part, to allow the first recessed part to move in a vertical direction of the slider, and to press the first recessed part to a widthwise outside of the slider, and a pair of second cylindrical parts, arranged in the pair of second recessed parts, to allow the pair of second recessed parts to move in a width direction of the slider, and to press the pair of second recessed parts in the vertical direction of the slider, respectively.

A buoyancy-enhanced loop drive system includes upper and lower gears, a helical drive loop extending around and rotatably engaging the upper and lower gears, and a tank configured to retain a liquid medium. An ascending side of the drive loop extends through the tank. In some embodiments, the drive loop includes a plurality of sections, and adjacent sections are rotatable with respect to each other about an axis normal to an end face of the sections. Additionally or alternatively, the ascending side of the drive loop advances through an inlet seal via an exit port defined in an exit wall oriented perpendicular to the exit direction. Additionally or alternatively, an intermediate plate is coupled to an inlet housing for rotation about a vertical axis, and to a stationary support structure for bi-directional translation.

Disclosed is a securing device for providing a movable unit of a linear guiding mechanism with additional safety in that the securing device prevents the movable unit from coming off a guiding rail in case of a bearing malfunction. The securing device comprises at least one securing portion and a coupling portion for coupling the at least one securing portion to the movable unit. The securing portion is engageable with the guiding rail in case of a failure of the movable unit.